rs397509425

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

The NM_021971.4(GMPPB):​c.553C>T​(p.Arg185Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000105 in 1,613,870 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R185H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

GMPPB
NM_021971.4 missense

Scores

8
10
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 2.18
Variant links:
Genes affected
GMPPB (HGNC:22932): (GDP-mannose pyrophosphorylase B) This gene is thought to encode a GDP-mannose pyrophosphorylase. The encoded protein catalyzes the conversion of mannose-1-phosphate and GTP to GDP-mannose, a reaction involved in the production of N-linked oligosaccharides. Alternatively spliced transcript variants encoding distinct isoforms have been described. [provided by RefSeq, Jan 2009]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.971
PP5
Variant 3-49722604-G-A is Pathogenic according to our data. Variant chr3-49722604-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 60543.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-49722604-G-A is described in Lovd as [Pathogenic]. Variant chr3-49722604-G-A is described in Lovd as [Pathogenic]. Variant chr3-49722604-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
GMPPBNM_021971.4 linkuse as main transcriptc.553C>T p.Arg185Cys missense_variant 5/9 ENST00000308388.7
GMPPBNM_013334.4 linkuse as main transcriptc.553C>T p.Arg185Cys missense_variant 5/8

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
GMPPBENST00000308388.7 linkuse as main transcriptc.553C>T p.Arg185Cys missense_variant 5/91 NM_021971.4 P1Q9Y5P6-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152216
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000359
AC:
9
AN:
250734
Hom.:
0
AF XY:
0.0000369
AC XY:
5
AN XY:
135520
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000145
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000177
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000103
AC:
15
AN:
1461536
Hom.:
0
Cov.:
44
AF XY:
0.0000110
AC XY:
8
AN XY:
727060
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000112
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000809
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152334
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74490
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000425
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Muscular dystrophy-dystroglycanopathy Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingRady Children's Institute for Genomic Medicine, Rady Children's Hospital San DiegoMay 29, 2019This variant has been previously reported as a homozygous change in 6 patients with hypotonia, muscle weakness, cataracts, and elevated serum creatine kinase (PMID: 23768512, 29054425). Functional studies have shown reduced alpha-dystroglycan glycosylation in muscle and fibroblasts of individuals with this variant (PMID: 23768512). It is present in the heterozygous state in the gnomAD population database at a frequency of 0.0036% (9/250,734) and thus is presumed to be rare. The c.553C>T (p.Arg185Cys) variant affects a highly conserved amino acid and is predicted by multiple in silico tools to have a deleterious effect on protein function. Based on the available evidence, the c.553C>T (p.Arg185Cys) variant is classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitterclinical testingGenetic Services Laboratory, University of ChicagoMay 23, 2017- -
Muscular dystrophy-dystroglycanopathy (congenital with brain and eye anomalies), type A14;C3809221:Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B14;C4518000:Autosomal recessive limb-girdle muscular dystrophy type 2T Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingUCLA Clinical Genomics Center, UCLAJan 28, 2014- -
Likely pathogenic, criteria provided, single submitterclinical testingInvitaeAug 16, 2022In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. Experimental studies are conflicting or provide insufficient evidence to determine the effect of this variant on GMPPB function (PMID: 23768512). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 60543). This missense change has been observed in individuals with clinical features of GMPPB-related conditions (PMID: 23768512, 25326637, 30684953, 32403337, 32404165). This variant is present in population databases (rs397509425, gnomAD 0.01%). This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 185 of the GMPPB protein (p.Arg185Cys). -
Inborn genetic diseases Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingAmbry GeneticsAug 07, 2017- -
Muscular dystrophy-dystroglycanopathy (congenital with intellectual disability), type B14 Pathogenic:1
Pathogenic, no assertion criteria providedliterature onlyOMIMJul 11, 2013- -
not provided Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingRevvity Omics, RevvitySep 27, 2022- -
Autosomal recessive limb-girdle muscular dystrophy type 2T Pathogenic:1
Pathogenic, no assertion criteria providedliterature onlyOMIMJul 11, 2013- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.51
BayesDel_addAF
Uncertain
0.025
T
BayesDel_noAF
Uncertain
0.050
CADD
Pathogenic
31
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.86
D;.;D
Eigen
Uncertain
0.55
Eigen_PC
Uncertain
0.46
FATHMM_MKL
Uncertain
0.90
D
LIST_S2
Pathogenic
1.0
.;D;D
M_CAP
Pathogenic
0.50
D
MetaRNN
Pathogenic
0.97
D;D;D
MetaSVM
Uncertain
0.25
D
MutationAssessor
Pathogenic
3.1
M;M;M
MutationTaster
Benign
1.0
D;D;D;D
PrimateAI
Uncertain
0.56
T
PROVEAN
Pathogenic
-7.1
D;D;D
REVEL
Pathogenic
0.67
Sift
Uncertain
0.0020
D;D;D
Sift4G
Uncertain
0.027
D;D;D
Polyphen
1.0
D;D;D
Vest4
0.95
MutPred
0.59
Loss of solvent accessibility (P = 0.0299);Loss of solvent accessibility (P = 0.0299);Loss of solvent accessibility (P = 0.0299);
MVP
0.92
MPC
1.7
ClinPred
0.89
D
GERP RS
3.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.80
gMVP
0.81

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs397509425; hg19: chr3-49760037; API